The present invention is directed to a method for the production of the (-) optical isomer of 2-substituted-ornithines.
2-Substituted-ornithines such as .alpha.-difluoromethylornithine have been reported to be inhibitors of the enzyme, ornithine decarboxylase, (J. Org. Chem., Vol. 44, No. 15, Bey, et al. (1979)). They have been reported to be useful in the treatment a number of disease states such as for example, psoriasis, benign prostatic hypertrophy, and as an antineoplastic agent, U.S. Pat. Nos. 4,743,691 and 4,496,588.
U.S. Pat. No. 4,496,588 teaches a method for resolving the optical isomers of these 2-substituted ornithines. The process comprises resolving a racemic 2-piperidone of the structure: ##STR1## wherein R represents the desired halogenated methyl radical, with (-) binaphthylphosphoric acid. Each of the optical isomers of the piperidone are then hydrolyzed separately to produce the desired optical isomer of the 2-substituted-ornithine.
Thus it would be a valuable contribution to the art to develop a process wherein the piperidone could be hydrolyzed and resolved in one step.